Sometimes when I disconnect my joystick from the computer, QMC2 drops my joystick settings from MAME, so I have to enter the input options in MAME and configure my inputs all over again. Here's one of the messages displayed by QMC2 when entering a game with my joystick disconnected: 11:00:19.348: stderr[#4]: Input: Dropping invalid input token JOYCODE_1_BOTãODEâNGULODEVISãOU
I understnd that QMC2 should not drop my input seetings even when my joystick is disconnected. If I want to configure it again for another device, I will do it myself. Losing all my input settings just because I have my joystick disconnected is terrible!
MAME itself drops joystick settings when you unplug, because it's assumed unplugging the controller means you want to use mouse and keyboard (and in fact back around 15 years ago people complained that that was exactly what they wanted).
I'm not sure anyone complained that they wanted that specifically. It was more that they screamed, "Help! I mapped Exit to a combination of gamepad buttons, and I started MAME without the gamepad connected and can't close it! Now I have to unplug the computer from the wall!" MAME's behaviour is designed to stop that from happening.